In a gas turbine, air pressurized in a compressor is mixed with fuel in a combustor to generate combustion gas that is a high-temperature fluid, and this combustion gas is introduced into a combustion gas flow passage of a turbine in which vanes and blades are alternately installed. The gas turbine rotates the blades and a rotor by the combustion gas flowing through the combustion gas flow passage. Thus, the gas turbine converts the energy of the combustion gas into rotary energy, so that electricity is taken out from a generator.
A clearance is provided between a transition piece of the combustor and a shroud of a first-stage vane of the turbine to prevent contact therebetween due to thermal elongation. In this clearance, a seal member is provided to prevent cooling air inside a turbine casing from leaking through the clearance into the combustion gas flow passage.
Examples of such a seal member include the transition piece seal disclosed in Japanese Patent Publication No. 2006-105076. This transition piece seal is disposed between a flange of the transition piece and a vane shroud. Each flange extends in a direction away from the combustion gas flow passage.